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Homo sapiens
26 Downloadable Samples
Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
One of the most important features of tumor microenvironment, imposing adverse effect on patient prognosis, is low oxygen tension. There are two types of hypoxia that may occur within tumor mass: chronic and cycling. Preliminary studies point at cycling hypoxia as being more relevant in induction of aggressive phenotype of tumor cells and radioresistance though little is known about the molecular mechanism of this phenomenon. Analysis of gene expression profile of human prostate (PC-3), ovarian (SK-OV-3) and melanoma (WM793B) cancer cells to expermental cycling (interchanging conditions of 1% and 21% oxygen) or chronic (1% oxygen) for 72 hours. Gene expression profiles were analyzed using U133 Plus 2.0 Array (Affymetrix) oligonucleotide microarrays. Data analysis revealed that globally gene expression profiles induced by the two types of hypoxia are similar and they strongly depend on the cell type.However, cycling hypoxia changes expression of lower number of genes in comparison to chronic one ( 3767 vs. 5954 probesets (p<0.001)) and to lower extent (lower fold changes). Analysis of hypoxia-regulated gene lists obtained using Random Variance Model t-test identified 253 probe sets (FC>2, p<0.001) common to all three cell lines, though no universal (changed throughout all analyzed cell lines) genes specifically influanced only by cycling hypoxia was selected. On the other hand, we identified such genes within particular one or two cell lines. Among them those related with EGF pathway seemed to be overrepresented (i.e. EPHA2, AREG, and HBEGF) and together with PLAU and IL-8 were mostly validated by Q-PCR.
Publication Title
Global gene expression profiling in three tumor cell lines subjected to experimental cycling and chronic hypoxia.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Homo sapiens
- 99 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The introduction of microarray techniques to cancer research brought great expectations for finding biomarkers that would improve patients treatment; however, the results of such studies are poorly reproducible and critical analyses of these methods are rare. In this study, we examined global gene expression in 97 ovarian cancer samples. Also, validation of results by quantitative RT-PCR was performed on 30 additional ovarian cancer samples. We carried out a number of systematic analyses in relation to several defined clinicopathological features. The main goal of our study was to delineate the molecular background of ovarian cancer chemoresistance and find biomarkers suitable for prediction of patients prognosis. We found that histological tumor type was the major source of variability in genes expression, except for serous and undifferentiated tumors that showed nearly identical profiles. Analysis of clinical endpoints [tumor response to chemotherapy, overall survival, disease-free survival (DFS)] brought results that were not confirmed by validation either on the same group or on the independent group of patients. CLASP1 was the only gene that was found to be important for DFS in the independent group, whereas in the preceding experiments it showed associations with other clinical endpoints and with BRCA1 gene mutation; thus, it may be worthy of further testing. Our results confirm that histological tumor type may be a strong confounding factor and we conclude that gene expression studies of ovarian carcinomas should be performed on histologically homogeneous groups. Among the reasons of poor reproducibility of statistical results may be the fact that despite relatively large patients group, in some analyses one has to compare small and unequal classes of samples. In addition, arbitrarily performed division of samples into classes compared may not always reflect their true biological diversity. And finally, we think that clinical endpoints of the tumor probably depend on subtle changes in many and, possibly, alternative molecular pathways, and such changes may be difficult to demonstrate.
Publication Title
Gene expression analysis in ovarian cancer - faults and hints from DNA microarray study.
Sample Metadata Fields
No sample metadata fields
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GSE2248- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Comparisons of expression profils of human undiferentiated ES cells and Mesenchymal ES cells
Publication Title
Derivation of multipotent mesenchymal precursors from human embryonic stem cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 22 Downloadable Samples
- Illumina HumanWG-6_V2_0_R2
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Tumour-initiating stem-like cells in human prostate cancer exhibit increased NF-κB signalling.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 22 Downloadable Samples
- Illumina HumanWG-6_V2_0_R2
Description
Human prostate CWR22 OT-tumor cells were prospectively purified for expression of various stem cell markers (TRA-1-60/CD151/CD166/EpCAM/CD44/2-Integrin). Unsorted total tumor cells or the additional marker positive cells that do not manifest stem-like characteristics were used as control. All these cells were subjected to molecular profiling of total RNA expression and the fold change data are tabulated according to S/TFE of the purified cells in relation to their control.
Publication Title
Tumour-initiating stem-like cells in human prostate cancer exhibit increased NF-κB signalling.
Sample Metadata Fields
Cell line
View Samples- Mus musculus
- 7 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
We aim to identify genes differentially expressed between mouse WT and COUP-TFI_Nex-Cre mutant cortices.
Publication Title
Postmitotic control of sensory area specification during neocortical development.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
We have developed efficient protocols for the derivation of mesenchymal precursors from hESCs. While previous protocols were based on mesodermal induction via co-culture of hESCs on OP9 mouse stroma (Barberi et al., PLoS Biology, 2005), our recent work shows the derivation of hESC derived mesenchymal precurors under feeder-free conditions. The data presented here show a large and highly signficant overlap in global gene expression profiles between hESC derived mesenchymal precursors derived under feeder-free conditions with those derived via OP9 co-culure and mesenchymal precurosrs isolated directly from the adult bone marrow.
Publication Title
Derivation of engraftable skeletal myoblasts from human embryonic stem cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 34 Downloadable Samples
- Illumina humanRef-8 v2.0 expression beadchip
Description
Here we present a strategy to adapt hESCs to high-throughput screening (HTS) conditions, resulting in an assay suitable for the discovery of small molecules that drive hESC self-renewal or differentiation. Use of this new assay has led to the identification of several currently marketed drugs and natural compounds promoting short-term hESC maintenance and compounds directing early lineage choice. Global gene expression analysis upon drug treatment reveals overlapping and novel pathways correlated to hESC self-renewal and differentiation. Our results demonstrate feasibility of hESC-based HTS and enhance the available repertoire of chemical compounds for manipulating hESC fate.
Publication Title
High-throughput screening assay for the identification of compounds regulating self-renewal and differentiation in human embryonic stem cells.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 16 Downloadable Samples
- Illumina humanRef-8 v2.0 expression beadchip
Description
The use of pluripotent stem cells in regenerative medicine and disease modeling is complicated by the variation in differentiation properties between lines. In this study, we characterized 13 human embryonic stem cell. (hESC) and 26 human induced pluripotent stem cell (hiPSC) lines to identify markers that predict neural differentiation behavior. At a general level, markers previously known to distinguish mouse ESCs from epiblast stem cells (EpiSCs) correlated with neural differentiation behavior. More specifically, quantitative analysis of miR-371-3 expression prospectively identified hESC and hiPSC lines with differential neurogenic differentiation propensity and in vivo dopamine neuron engraftment potential. Transient KLF4 transduction increased miR-371-3 expression and altered neurogenic behavior and pluripotency marker expression. Conversely, suppression of miR- 371-3 expression in KLF4-transduced cells rescued neural differentiation propensity. miR-371-3 expression level therefore appears to have both a predictive and a functional role in determining human pluripotent stem cell neurogenic differentiation behavior.
Publication Title
miR-371-3 expression predicts neural differentiation propensity in human pluripotent stem cells.
Sample Metadata Fields
Sex, Cell line
View Samples- Homo sapiens
- 20 Downloadable Samples
Description
The development of the central nervous system (CNS) depends on the orchestrated generation of neurons and glia from neural stem cells (NSCs). Although NSCs generate both cell types, they are produced sequentially as neurons are born first and glia later. In humans, this timing is extremely protracted and the underlying mechanisms remain unknown. Deriving glial cells such as astrocytes from human pluripotent stem cells requires 3-6 months of differentiation, greatly impeding their use in human disease modeling and regenerative medicine. Here, we report that expression of the transcription factor nuclear factor IA (NFIA) is sufficient to trigger glial competency in highly neurogenic NSCs and enables the derivation of human astrocytes within 10-12 days. NFIA-induced astrocytes are functional and shown to promote synaptogenesis, protect neurons and generate calcium transients. The mechanism of NFIA-induced glial competency involves rapid but reversible chromatin remodeling, demethylation of the GFAP promoter and a striking effect on the cell cycle. NFIA titration and pharmacological studies indicate that acquisition of a glial-compatible G1 length is critical for achieving glial competency. Our results offer mechanistic insights into human glial competency and enable the routine use of astrocytes for studying human development and disease. Overall design: The timecourse consists of 4 timpoints. Day 0 (d0) represents neurogenic LTNSCs, day 3 (d3) represents overexpression of NFIA with doxycycline and cells were harvested in bulk, day 6 (d6) represents cells sorted for CD44 while NFIA is overexpressed, day 9 (d9) represents CD44+ sorted cells replated in culture without the addition of doxycyline to downregulate NFIA and day 12 (d12) represents the same cultures in d9, but with 3 additional days of no doxycycline treatment. Each timepoint has a minimum of 3 biological replicates. Rosette cells (H9 d0) and neurons (Dapt) were profiled as controls where rosettes were one sample and neurons were performed in duplicate.
Publication Title
NFIA is a gliogenic switch enabling rapid derivation of functional human astrocytes from pluripotent stem cells.
Sample Metadata Fields
No sample metadata fields
View Samples